A number of electronic devices have graphical user interfaces (GUIs). Such devices include, for example, personal computers (PCs), television sets and mobile telephones handsets. The user may interact with the device via the GUI using a user interface, for instance a touch sensitive pad, a keyboard, a mouse, a joystick or a remote control. Many factors determine the most appropriate choice of user interface for a device, such as ease and speed of operation and the environment in which the device is used. The use of a mouse is suited to the selection of icons when using a desk-top personal computer, however it is not so useful when used to make selections when using a digital television set. For this, a remote control unit having several keys is most convenient.
However, there are problems with using a key- or button-based control units as will now be explained with reference to digital television.
Digital television provides a variety of new services as compared with analogue television. It allows the user to transmit and receive signals via a set-top box and to interact with service providers. The user may now access the Internet in a similar way that is already available on a PC. For example, a user may navigate web pages by selecting hypertext links. The process of selecting a particular link involves moving a focus between links and activating a selection. In a PC-based system, this process is realised by positioning a mouse pointer over the link and pressing the mouse button. To indicate that the focus has moved to the link, the shape of the mouse pointer changes or the link is highlighted, for instance by changing colour or displaying a box around it.
The set-top box/television set system is often controlled using a remote control unit similar to that used with an existing analogue television. The remote control is usually provided with a set of dual-state arrow keys—up, down, right, left—allowing orthogonal movement about a menu or screen.
However, the remote control unit is not particularly suited to the selection of links in a web page using a pointer because it has fewer degrees of freedom than a mouse. Links may be positioned in such a way that the quickest way to reach them is by going diagonally across a viewing window. Furthermore, links may be sparsely separated and so repeated pressing of the keys is required to reach a link.
Moreover, the web page may be larger than the viewing window and so links may be located outside the viewing window.
The present invention seeks to solve these problems.